SplitBridge Reserve

You're on the list. Thank you!

We'll email you when there's real news, not before. If you know your indoor unit's model number, send it to splitbridge@binarybeach.tech. It helps us build the compatibility list.

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Deposits aren't open yet. We'll email you the reservation link as soon as they are. Nothing is charged until then.

Reservation received. Thank you!

Stripe will email you a receipt for the $10 deposit. Estimated shipping is the second half of 2027, and we'll email you before then if that changes. You can cancel anytime before shipping for a full refund: just write to splitbridge@binarybeach.tech.

In development · Designed in Honolulu

Your mini‑split, on your Wi‑Fi. No cloud.

A small adapter that plugs into the service connector inside your indoor unit. Compatible with Mitsubishi Electric units with a CN105 connector, with Daikin (S21) next. It shows up in Home Assistant and runs on your own network.

$89 per unit

Reserve one Just keep me posted

Reservation: $10 refundable deposit toward the $89 price · estimated shipping second half of 2027 · cancel anytime before shipping for a full refund · Reservation terms

Illustration of the adapter: a small rounded box with a status light and a short cable ending in a plug. SplitBridge
Illustration · not the final design

How it works

  1. Pop the front cover

    Switch the unit off at the breaker and lift the front panel. The port is on the indoor unit's control board. We'll publish photo guides by model.

  2. Plug into the port

    The cable fits the CN105 connector on compatible Mitsubishi Electric units. A Daikin S21 cable comes next. It runs on the unit's own low-voltage supply. No batteries, no mains wiring.

  3. It appears in Home Assistant

    Join it to your Wi-Fi and Home Assistant finds it. Set mode, temperature and fan from there. Everything stays on your network.

Why not the maker's adapter?

It works, but it costs more per unit and runs through the maker's cloud.

Maker's Wi-Fi adapterSplitBridge
Price per indoor unit~$2291$89 (target)
AccountCloud account requiredNone
Control runs throughThe maker's cloudYour own network
Internet goes downDepends on the maker's cloudKeeps working at home
SoftwareThe maker's app, which can change under you2Open-source firmware (ESPHome), Home Assistant
  1. Mitsubishi Electric PAC-USWHS002-WF-2 list price (GotDuctless listing, checked Oct 15, 2026). One adapter per indoor unit.
  2. Mitsubishi says older kumo cloud adapters don't work with its new Comfort app (App Store listing).

Reserve one, or just keep in touch

Three quick questions. Your answers tell us which units to support first.

Brand of your indoor units
How many indoor units?

You need one adapter per indoor unit (the part on the wall or ceiling).

Tell us more (optional)
Do you use Home Assistant?

Reservation: $10 refundable deposit toward the $89 price. Cancel anytime before shipping for a full refund. Terms below.

Reservation terms

  • Deposit: $10 refundable deposit toward the $89 price. We charge the balance only when your order is ready to ship.
  • Estimated shipping: second half of 2027. SplitBridge is a pre-production product. If that date changes, we'll email you before it passes, and you can cancel for a full refund.
  • Refunds: cancel any time before shipment by replying to your confirmation email or writing to splitbridge@binarybeach.tech. We refund to your original payment method within 7 working days. If we can't complete FCC authorization or can't ship the product, we'll cancel and refund you automatically.
  • Title: Binary Beach LLC keeps title to the device until it ships to you.

FCC notice: This device is subject to the rules of the Federal Communications Commission (FCC). Delivery to you is conditional upon successful completion of the applicable FCC equipment authorization process (a Supplier's Declaration of Conformity under 47 CFR Part 15). FCC rules do not address the applicability of consumer protection, contractual, or other provisions under federal or state law. If we cannot complete FCC authorization, we will not ship, and we will refund 100% of your payment to your original payment method within 7 working days of that decision. You may also cancel at any time before shipment for a full refund.

We only use your email to send SplitBridge updates. Unsubscribe anytime.

Questions

Which units will it work with?

First: Mitsubishi Electric indoor units with a CN105 connector. Next: Daikin units with an S21 port. Many units from both brands have one, but not all. We'll publish a compatibility list by model number before anything ships. Not sure about yours? Put the model number in the form and we'll check.

Is it safe for my AC?

It plugs into the low-voltage service port, the same port the makers' own Wi-Fi adapters use. There's no mains wiring, and you switch the unit off at the breaker before opening it. We're testing on real units for weeks before anything ships, and we'll publish what we find. We can't speak for your manufacturer's warranty, so check its terms before you install.

When does it ship?

Estimated shipping: second half of 2027. SplitBridge is a pre-production product: the design is underway, real-unit testing comes next, and it needs FCC authorization before it can ship. If that date changes, we'll email you before it passes, and you can cancel for a full refund.

What does a reservation mean?

It's a $10 refundable deposit toward the $89 price shown on this page, and it holds your spot in the first batch. You can cancel any time before shipment for a full refund to your original payment method within 7 working days. When it's ready, we'll confirm how many units you want and charge the balance only then. Delivery depends on FCC authorization: if we can't complete it, we'll cancel and refund you automatically. Binary Beach LLC keeps title to the device until it ships. Full reservation terms.

Do I need Home Assistant?

For version 1, yes. It connects to Home Assistant through ESPHome, on your own network. Matter support (for Apple Home and Google Home) is planned, not promised. If you don't use Home Assistant, sign up anyway and say so. It helps us decide what to build next.

Is it open source?

The firmware is built on open-source ESPHome (GPL), and we'll publish its source so you can rebuild or reflash it yourself. Whether the hardware design will be open too is still undecided.

Couldn't I build one myself?

You can, and hobbyists have done it for years with open CN105 and S21 projects. SplitBridge is for people who'd rather not source a board, make a cable and flash firmware. It comes assembled, in a case, with the right connector for your brand.